l-Methionine Production

Abstract

L-Methionine has been used in various industrial applications such as the production of feed and food additives and has been used as a raw material for medical supplies and drugs. It functions not only as an essential amino acid but also as a physiological effector, for example, by inhibiting fat accumulation and enhancing immune response. Producing methionine from fermentation is beneficial in that microorganisms can produce L-methionine selectively using eco-sustainable processes. Nevertheless, the fermentative method has not been used on an industrial scale because it is not competitive economically compared with chemical synthesis methods. Presented are efforts to develop suitable strains, engineered enzymes, and alternative process of producing L-methionine that overcomes problems of conventional fermentation methods. One of the alternative processes is a two-step process in which the L-methionine precursor is produced by fermentation and then converted to L-methionine by enzymes. Directed efforts toward strain development and enhanced enzyme engineering will advance industrial production of L-methionine based on fermentation.

Untargeted Metabolomics Analysis Revealed Lipometabolic Disorders in Perirenal Adipose Tissue of Rabbits Subject to a High-fat Diet

“…L-methionine produces methionine, and it functions not only as an essential amino acid but also as a physiological effector [59]. We found higher levels of L-methionine in HFD than in SND rabbits.…”

Genomics Insights into Pseudomonas sp. CG01: An Antarctic Cadmium-Resistant Strain Capable of Biosynthesizing CdS Nanoparticles Using Methionine as S-Source

“…The direct sulfhydrylation pathway has been described as the main Met synthesis pathway in the Pseudomonas genus [ 85 ], and the critical gene ( metZ ) was present in all genomes analyzed ( Figure 6 b and Figure 7 ). Before Met formation, this pathway involves the direct formation of homocysteine catalyzed by the enzyme O-succinylhomoserine sulfhydrylase ( metZ , EC:2.5.1.-), using O-succinyl-homoserine as substrate ( Figure 6 b), or the synthesis of homocysteine using O-acetyl-homoserine and sulfide (present in 8 strains) catalyzed by the O-acetyl-L-homoserine sulfhydrolase ( metY , EC: 2.5.1.49) [ 84 , 85 , 97 , 101 , 108 , 109 , 110 ].…”

Metabolic engineering of E. coli for the production of O-succinyl-l-homoserine with high yield

“…On this basis, an E. coli CJM002 mutant was constructed by overexpressing thrA fbr (insensitive to l-threonine), which further increased the OSH titer by 14% in flask culture (Shin et al 2010). Although the OSH production with high titer was achieved through fed-batch fermentation, the OSH yield from glucose in the reported strains was still lower than the theoretical yield (Shim et al 2017). Furthermore, the addition of amino acids such as l-methionine, l-threonine, and l-isoleucine to the culture medium required by these auxotrophic strains increased the fermentation cost.…”